GSK announces avian flu vaccine trials

Seizing on yesterday's mixed results for Sanofi Pasteur's avian flu vaccine (which we wrote about in our last post), GSK announced today the launch of avian flu vaccine trials of its own. Here's Reuters report on the announcement and the GSK press release.

As we noted yesterday, the key problem with the Sanofi vaccine is the very high doses needed to generate a satisfactory immune response. GSK is optimistic that they won't have similar problems because of the addition of adjuvants, ingredients that amplify the immune system's response to a vaccine. One trial includes a common alum adjuvant, the other uses GSK's own AS04 adjuvant (which also is included in its HPV vaccine, among other GSK products). Both trials have enrolled approximately 400 volunteers.

Describing the AS04 adjuvant trial, the GSK press release explains...

"GSK is hopeful that a vaccine formulated with this novel adjuvant will further enable individual’s immune system to respond to different H5N1 virus strains, offering a broader protection against the threat of a pandemic. GSK’s novel adjuvant technology is also expected to further reduce the amount of antigen needed per dose, increasing the number of doses the company could make available worldwide."

Hope and expectation are both nice, but the data will be the final judge. Preliminary results are expected by the end of summer.